Getting the most from your Therma-Dome Products

Looking up at open cover

Assembling your Therma-Dome Cover

Plan Ahead

Before assembling your Therma-Dome insulating cover, ensure that you will be able to get it through the attic opening if you intend to assemble the cover outside of the attic. Overhead obstructions near the attic access may necessitate that the cover be assembled in the attic.

Prepare the area

Prepare the surface where the cover will be installed by brushing any dust and dirt off of the attic floor in the installation area. For lift-off covers, the gasket will be most effective if it has a flat and clean surface to seal against. If the cover is being installed with stationary sidewalls (such as the Versa-Dome or Whole-House Fan Cover), the adhesive and tape will need a clean and clear surface to bond and seal with.

Seal the small gaps

The cover will be part of a system that blocks air transfer between the unconditioned space in your attic and the conditioned space in your home. For the most effective seal, caulk or tape any exposed seams in the framing and attic floor. Leaving these gaps unsealed will allow air to pass around the cover, minimizing its effectiveness.

Seal the Big Gaps

Ensure that your attic stairs or whole-house fan louvers close tightly. The additional “dead air” pocket between the cover and the pull-down door or closed louvers will offer additional insulation value.

Pull-Down Attic Stairs

Make sure that the attic door closes tightly. For additional sealing effectiveness, consider adding self-sticking weatherstrip gasket around the door where it closes against the trim.

Whole-House Attic Fans

A magnetic or other living-area side cover for a the whole-house fan louvers will provide additional insulation value, and will also serve as a visible reminder to not engage the attic fan when the Therma-Dome cover is in place.

Using your Therma-Dome Cover

Therma-Dome covers are designed to give you years of reliable service.

When accessing your attic, be sure to unstrap the Velcro hold-downs from both ends of the cover before lifting the cover out of the way. Place the cover where it will not be at risk of damage by stepping on it or striking it with an item being moved into or out of the attic.

Do not use the Velcro straps as handles to assist in getting in or out of the attic. These straps are not weight-bearing and are intended only to hold the cover in place and maintain compression on the weatherstrip gasket.

Repairing damage to your Therma-Dome cover

Should your cover become damaged, it can be repaired using materials that you can find at most building supply stores. If the damage is a scrape that causes the foil face to peel, simply use foil tape to cover any exposed foam.

Duct tape is not recommended for assembly or repair of the cover, as the extreme hot/cold temperature cycles in the attic will cause most tapes, including duct tape, to disintegrate.

If the damage is more severe, such as a puncture or gouge, you can use spray foam from a can to fill any voids. Once the new foam has fully cured, use foil tape to cover the exposed foam.

If the damage is a break, you can use spray foam or foam-safe construction project adhesive (such as, but not limited to, Loctite PL200) to bond the broken pieces. Use foil tape to hold the pieces together as the adhesive dries. Once dry, seal the seam with foil tape.